/*
 * Copyright 2009 Original Author(s)
 * 
 * This file is part of Kommando
 * 
 * Kommando is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * Kommando is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with Kommando.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.kommando.core.search;

import java.util.Comparator;

/**
 * Strategy for sorting {@link Result}s
 * <p>
 * Defaults should always be first, then sort by score, if score is equal, sort by name
 * 
 * @author Peter De Bruycker
 */
public class ResultComparator implements Comparator<Result<?>> {

    @Override
    public int compare(Result<?> r1, Result<?> r2) {
        if (r1 instanceof DefaultResult) {
            return 1;
        }

        if (r2 instanceof DefaultResult) {
            return -1;
        }

        if (r1 instanceof ScoredResult && r2 instanceof ScoredResult) {
            ScoredResult<?> scoredResult1 = (ScoredResult<?>) r1;
            ScoredResult<?> scoredResult2 = (ScoredResult<?>) r2;

            // TODO if score is equal, sort by name

            return Float.compare(scoredResult2.getScore(), scoredResult1.getScore());
        }

        throw new IllegalArgumentException("results of unexpected types");
    }

}
